There are many different kinds of specialized generators for extracting energy from nature one way or another, including tidal generators, ocean current, wave, and temperature differential generators, lightening generators, waterfall generators, and even a gyro generator.
All of these apparatuses are specialized in their requirements for an energy source, some relying on hot water from thermal wells, others needing a 20-foot tide differential. Current generators require water currents, wave generators require waves, and so forth.
However, one source of energy that is virtually universal is the temperature differential. Geothermal heat, solar heat, waste combustion exhaust gas, industrial heat discarded as a by-product, etc. are sources of thermal differentials when paired specifically with lower temperature sources as cool ocean or river currents or even with wind. Stratified ocean layers, and night/day differentials in deserts offer energy opportunities. All that is needed to produce energy, aside from a mechanism to do it, is a temperature differential between two masses as set out in the second law of thermodynamics.
A government effort dubbed "OTEC", for "Ocean Thermal Energy Conversion" has achieved limited success with ocean thermal differentials, reaching at least break-even outputs, which is rather impressive considering the limitation on efficiency predicted by the second law of thermodynamics based on the relatively narrow temperature spread. Nonetheless this system is based on the continuous availability of the hot and cold temperature sources and as a very large fixed plant, no doubt must be worked all the time to have a hope of breaking even commercially.
There is a need for a versatile energy producing system buildable for one or more houses or cities capable of taking advantage of these limitless polarized temperature combinations to efficiently produce clean, competitive energy from mixed and erratic sources. Along these lines little attention has been paid to the use of buoyancy generators, especially in regard to their use transducing energy from thermal differentials. Buoyancy wheels or turbines have been suggested for limited applications in which gas is escaping from the sea floor, but have not been considered realistic for generalized transduction of thermal energy, which would require the creation of a man-made bubble path for a circulating gas.
Examples of buoyancy wheels are shown by U.S. Pat. No. 4,363,212, issued Dec. 14, 1982, and another example is shown in U.S. Pat. No. 4,981,015 issued Jan. 1, 1991. Both disclose flotation wheels whose design requires more energy input than the output energy they would yield, relying on a nondisclosed source of flotation energy having no creation cost.